v1.5.1

• Fix a panic on tier2 when not using any wasm extension.
• Fix a thread leak on metering GRPC emitter
• Rollback scheduler optimisation: different stages can run concurrently if they are schedulable. This will prevent taking much time to execute when restarting close to HEAD.
• Add substreams_tier2_active_requests and substreams_tier2_request_counter prometheus metrics
• Fix the tools tier2call method to make it work with the new 'generic' tier2 (added necessary flags)